1. Field of the Invention
This invention relates to apparatus which detects the operator's visual axis and controls an optical apparatus on the basis of the detected information.
Also, this invention relates to a silver salt or video camera, and particularly ensures that the focus of the camera will be adjusted to an object the operator is gazing at.
2. Related Background Art
Auto-focus: single-lens reflex cameras recently available in the market include ones having a plurality of distance measuring view fields (detection view fields). The advent of cameras of such type, as compared with conventional cameras which effect distance measurement only in the center of the image field, has made it unnecessary to perform the operation of so-called AF lock which is the re-framing after focusing to an object. Accordingly, the snapshooting capability is improved and particularly, the degree of freedom of framing to a moving object is considerably increased. This is also the advantage that even photographers who are not accustomed to cameras have become able to take photographs without being nervous about focusing. Attempts are being made to further increase the number of distance measuring view fields to improve the simplicity of photographing.
Now, when a number of distance measuring view fields are provided, to make the most advantage thereof, always an optimal distance measuring view field must be selected and focus adjustment must be made on the basis of this information. For this purpose, the technique of detecting the photographer's visual axis position and focusing the camera on the object in that portion is disclosed in Japanese Laid-Open Patent Application Nos. 1-241511 and 2-32312.
However, there is a problem which cannot be solved by a construction in which the focus follows the visual axis position. That is, the movement of the visual axis is very great in order to view an entire object, and the visual axis position detected at a certain moment, if it is at least a point on the object, is not always a point on the object that is best suited for focusing. In that sense, even if a position suited for focusing is set on the basis of the result of the detection at a certain moment, it does not always coincide with the photographer's intention, and it is desired to set conditions with even the physiological behavior of perception taken into account.